A Barnes & Noble Nook Color eReader, left, is shown next to a Nook Simple Touch eReader, right, on display at a Best Buy in Mountain View, Calif.,in this April 2012 file photo. According to Hamm, buying a floor model after it's been on display can be a great deal, as long as you make sure it works properly.

When you go shopping for many items, from DVD players to vacuum cleaners, you’ll often see that the model is available for you to look at and (often) to try out. I’ve certainly browsed through the menus of DVD players at electronic stores, opened the doors on washing machines at appliance stores, and played with an iPad at our local warehouse club.

Floor models give you a great idea of how something works, but they can also provide a great discount for you if you’re shopping at the right time.

When a model is either replaced with an upgraded version or moved to a less-featured area of the store, the store is often left with that floor model that you once played with. It’s now slightly used, so it usually can’t be sent back to the factory and it can’t be repackaged as new.

Digital cameras are a wonderful example of how you can save money with floor models and discontinued models. Digital camera models rotate pretty regularly and many stores end up putting the floor models of the older cameras out there for sale at a pittance.

However, buying floor models can be risky. You don’t know what has been done to them in the past. They’ve often been out for display for months, meaning people have done all sorts of things to them.

Because of that, there are a few simple rules I use when evaluating whether to buy a floor model.

First, is the discount steep enough that it’s worth some minor potential hassles? For example, if a floor model is $30 and a new version is $40, I’m not going to bother with the discounted one because $10 is not worth the potential effort in having to deal with a return. I want to see a discount that’s at least 50% off, and if it’s a major item, I want to be saving hundreds.

Why? You’re essentially buying a used item here. The chances of discovering a problem are much higher with a floor model, and if you do find a problem you have to deal with returning it.

Speaking of returns, make absolutely sure you understand what the store’s policy is in terms of returning it. Some stores won’t let you return them at all. Others offer a very short period for returns.

I would never buy a floor model that I couldn’t return unless the thing was nearly free. If you can’t return the item, you’re very likely going to be stuck with a complete lemon.

You should also ask if they’ve done any cleanup on the item before selling it. Did they reformat the hard drive on the computer? Did they clean the item? Or did they just chuck it into a box and slap a price tag on it? A bit of effort in checking out the item goes a long way.

One final tip: ask if you can try out the item before you buy it. Do they have a place you can plug it in? Can you take it out of the box (if it’s got one) and see if it works?

This last one is pretty close to a deal-breaker for me. If they want me to buy a used item without any way to verify that it actually works, I’m walking away. If they won’t let me try it and they don’t have a return policy, I’m not taking it with me unless it is absolutely free.

Even with these policies, I’ve still found and purchased quite a few floor models, including my current digital camera. All of them had huge discounts and only one had any significant problems (which the store took care of, actually). If the store has decent policies and you have a chance to try the item, consider a floor model. It can save you some cash.

This post is part of a yearlong series called “365 Ways to Live Cheap (Revisited),” in which I’m revisiting the entries from my book “365 Ways to Live Cheap,” which is available at Amazon and at bookstores everywhere. Images courtesy of Brittany Lynne Photography, the proprietor of which is my “photography intern” for this project.

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